import re
from typing import Callable

from starlette.applications import Starlette
from starlette.middleware import Middleware
from starlette.middleware.sessions import SessionMiddleware
from starlette.requests import Request
from starlette.responses import JSONResponse
from starlette.routing import Mount, Route
from starlette.testclient import TestClient

TestClientFactory = Callable[..., TestClient]


def view_session(request: Request) -> JSONResponse:
    return JSONResponse({"session": request.session})


async def update_session(request: Request) -> JSONResponse:
    data = await request.json()
    request.session.update(data)
    return JSONResponse({"session": request.session})


async def clear_session(request: Request) -> JSONResponse:
    request.session.clear()
    return JSONResponse({"session": request.session})


def test_session(test_client_factory: TestClientFactory) -> None:
    app = Starlette(
        routes=[
            Route("/view_session", endpoint=view_session),
            Route("/update_session", endpoint=update_session, methods=["POST"]),
            Route("/clear_session", endpoint=clear_session, methods=["POST"]),
        ],
        middleware=[Middleware(SessionMiddleware, secret_key="example")],
    )
    client = test_client_factory(app)

    response = client.get("/view_session")
    assert response.json() == {"session": {}}

    response = client.post("/update_session", json={"some": "data"})
    assert response.json() == {"session": {"some": "data"}}

    # check cookie max-age
    set_cookie = response.headers["set-cookie"]
    max_age_matches = re.search(r"; Max-Age=([0-9]+);", set_cookie)
    assert max_age_matches is not None
    assert int(max_age_matches[1]) == 14 * 24 * 3600

    response = client.get("/view_session")
    assert response.json() == {"session": {"some": "data"}}

    response = client.post("/clear_session")
    assert response.json() == {"session": {}}

    response = client.get("/view_session")
    assert response.json() == {"session": {}}


def test_session_expires(test_client_factory: TestClientFactory) -> None:
    app = Starlette(
        routes=[
            Route("/view_session", endpoint=view_session),
            Route("/update_session", endpoint=update_session, methods=["POST"]),
        ],
        middleware=[Middleware(SessionMiddleware, secret_key="example", max_age=-1)],
    )
    client = test_client_factory(app)

    response = client.post("/update_session", json={"some": "data"})
    assert response.json() == {"session": {"some": "data"}}

    # requests removes expired cookies from response.cookies, we need to
    # fetch session id from the headers and pass it explicitly
    expired_cookie_header = response.headers["set-cookie"]
    expired_session_match = re.search(r"session=([^;]*);", expired_cookie_header)
    assert expired_session_match is not None
    expired_session_value = expired_session_match[1]
    client = test_client_factory(app, cookies={"session": expired_session_value})
    response = client.get("/view_session")
    assert response.json() == {"session": {}}


def test_secure_session(test_client_factory: TestClientFactory) -> None:
    app = Starlette(
        routes=[
            Route("/view_session", endpoint=view_session),
            Route("/update_session", endpoint=update_session, methods=["POST"]),
            Route("/clear_session", endpoint=clear_session, methods=["POST"]),
        ],
        middleware=[
            Middleware(SessionMiddleware, secret_key="example", https_only=True)
        ],
    )
    secure_client = test_client_factory(app, base_url="https://testserver")
    unsecure_client = test_client_factory(app, base_url="http://testserver")

    response = unsecure_client.get("/view_session")
    assert response.json() == {"session": {}}

    response = unsecure_client.post("/update_session", json={"some": "data"})
    assert response.json() == {"session": {"some": "data"}}

    response = unsecure_client.get("/view_session")
    assert response.json() == {"session": {}}

    response = secure_client.get("/view_session")
    assert response.json() == {"session": {}}

    response = secure_client.post("/update_session", json={"some": "data"})
    assert response.json() == {"session": {"some": "data"}}

    response = secure_client.get("/view_session")
    assert response.json() == {"session": {"some": "data"}}

    response = secure_client.post("/clear_session")
    assert response.json() == {"session": {}}

    response = secure_client.get("/view_session")
    assert response.json() == {"session": {}}


def test_session_cookie_subpath(test_client_factory: TestClientFactory) -> None:
    second_app = Starlette(
        routes=[
            Route("/update_session", endpoint=update_session, methods=["POST"]),
        ],
        middleware=[
            Middleware(SessionMiddleware, secret_key="example", path="/second_app")
        ],
    )
    app = Starlette(routes=[Mount("/second_app", app=second_app)])
    client = test_client_factory(app, base_url="http://testserver/second_app")
    response = client.post("/update_session", json={"some": "data"})
    assert response.status_code == 200
    cookie = response.headers["set-cookie"]
    cookie_path_match = re.search(r"; path=(\S+);", cookie)
    assert cookie_path_match is not None
    cookie_path = cookie_path_match.groups()[0]
    assert cookie_path == "/second_app"


def test_invalid_session_cookie(test_client_factory: TestClientFactory) -> None:
    app = Starlette(
        routes=[
            Route("/view_session", endpoint=view_session),
            Route("/update_session", endpoint=update_session, methods=["POST"]),
        ],
        middleware=[Middleware(SessionMiddleware, secret_key="example")],
    )
    client = test_client_factory(app)

    response = client.post("/update_session", json={"some": "data"})
    assert response.json() == {"session": {"some": "data"}}

    # we expect it to not raise an exception if we provide a bogus session cookie
    client = test_client_factory(app, cookies={"session": "invalid"})
    response = client.get("/view_session")
    assert response.json() == {"session": {}}


def test_session_cookie(test_client_factory: TestClientFactory) -> None:
    app = Starlette(
        routes=[
            Route("/view_session", endpoint=view_session),
            Route("/update_session", endpoint=update_session, methods=["POST"]),
        ],
        middleware=[Middleware(SessionMiddleware, secret_key="example", max_age=None)],
    )
    client: TestClient = test_client_factory(app)

    response = client.post("/update_session", json={"some": "data"})
    assert response.json() == {"session": {"some": "data"}}

    # check cookie max-age
    set_cookie = response.headers["set-cookie"]
    assert "Max-Age" not in set_cookie

    client.cookies.delete("session")
    response = client.get("/view_session")
    assert response.json() == {"session": {}}


def test_domain_cookie(test_client_factory: TestClientFactory) -> None:
    app = Starlette(
        routes=[
            Route("/view_session", endpoint=view_session),
            Route("/update_session", endpoint=update_session, methods=["POST"]),
        ],
        middleware=[
            Middleware(SessionMiddleware, secret_key="example", domain=".example.com")
        ],
    )
    client: TestClient = test_client_factory(app)

    response = client.post("/update_session", json={"some": "data"})
    assert response.json() == {"session": {"some": "data"}}

    # check cookie max-age
    set_cookie = response.headers["set-cookie"]
    assert "domain=.example.com" in set_cookie

    client.cookies.delete("session")
    response = client.get("/view_session")
    assert response.json() == {"session": {}}